The project's objective is the construction of a complete restriction map of the DNA in the yeast nuclear genome. All 5000 sites for the enzyme EcoRI will be assigned quantitative coordinates on the seventeen yeast chromosomes. Once the physical map is constructed, the positions of a sufficient number of genetically mapped genes will be determined to allow superposition of the genetic and physical maps. In order to accomplish the physical mapping, a new method of analyzing extremely complex DNA sequences will be developed. The genome will be randomly sampled using conventional recombinant DNA techniques. With the aid of an automated data acquisition system, the sizes of the EcoRI fragments present in approximately 3000 30 kilobase clones will be determined. This data set will then be interpreted to yield a genomic restriction map with the aid of a computer-implemented topological algorithm.